Free Online Calculators
Quick, accurate calculators for everyday tasks — no signup required.
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engineering
Force Resolution Calculator
Resolve a force into horizontal and vertical components
Moment Calculator
Calculate moments about a point from multiple forces
Resultant Force Calculator
Find the resultant of multiple forces with magnitude and direction
Centroid Calculator
Calculate the centroid of composite shapes (rectangles and circles)
Area Moment of Inertia Calculator
Calculate the second moment of area for common cross-sections
Parallel Axis Theorem Calculator
Apply the parallel axis theorem to find moment of inertia about any axis
Friction Calculator
Calculate static and kinetic friction forces for common material pairs
Truss Analysis Calculator
Solve member forces and reactions for Warren, Pratt, and Howe trusses
Projectile Motion Calculator
Calculate range, max height, and time of flight for projectile motion
Circular Motion Calculator
Calculate centripetal acceleration, force, angular velocity, and period
Work-Energy Calculator
Calculate kinetic energy, potential energy, and work done by a force
Impulse-Momentum Calculator
Calculate impulse, momentum change, and average force
Angular Momentum Calculator
Calculate angular momentum, torque, and conservation scenarios
Simple Harmonic Motion Calculator
Calculate period, frequency, and max velocity for spring-mass systems
Gear Ratio Calculator
Calculate gear ratios, output RPM, and torque for single or multi-stage gear trains
Stress Calculator
Calculate normal stress (σ = F/A) and shear stress (τ = V/A) with unit conversions
Strain Calculator
Calculate axial strain, percentage strain, and lateral strain with Poisson's ratio
Hooke's Law Calculator
Solve for stress, modulus, or strain using Hooke's Law for normal and shear loading
Mohr's Circle Calculator
Calculate principal stresses, maximum shear stress, and principal angle from a 2D stress state
Beam Bending Calculator
Calculate maximum deflection, bending moment, and reactions for simply supported, cantilever, and fixed-fixed beams
Beam Bending Stress Calculator
Calculate bending stress (σ = My/I) for rectangular, circular, and I-beam cross-sections
Torsion Calculator
Calculate shear stress and angle of twist for solid and hollow circular shafts under torsion
Column Buckling Calculator
Calculate Euler critical buckling load, critical stress, and slenderness ratio for columns
Thermal Stress Calculator
Calculate thermal stress for constrained members and free thermal expansion due to temperature change
Stress Concentration Calculator
Calculate stress concentration factors (Kt) and peak stress for plates with holes, notches, and shaft fillets
Factor of Safety Calculator
Calculate static factor of safety and fatigue life using Goodman and Soderberg criteria
Combined Loading Calculator
Calculate Von Mises stress, max shear, and principal stresses under combined axial, bending, and torsional loads
Ideal Gas Law Calculator
Solve for P, V, n, or T using PV = nRT with unit conversions for pressure, volume, and temperature
Isentropic Process Calculator
Calculate isentropic process relations between states using P, V, T and the specific heat ratio γ
Carnot Efficiency Calculator
Calculate Carnot cycle efficiency, net work, and required temperatures for a given efficiency
Otto Cycle Calculator
Calculate Otto cycle thermal efficiency and state-point temperatures and pressures from compression ratio
Diesel Cycle Calculator
Calculate Diesel cycle thermal efficiency from compression ratio, cutoff ratio, and specific heat ratio
Rankine Cycle Calculator
Calculate Rankine cycle efficiency, turbine work, pump work, and heat input from state-point enthalpies
Heat Engine Calculator
Solve for Q_in, Q_out, W_net, or efficiency given any two of the four heat engine quantities
Refrigeration COP Calculator
Calculate coefficient of performance for refrigerators and heat pumps, including Carnot COP from temperatures
Psychrometric Calculator
Calculate humidity ratio, dew point, enthalpy, and specific volume from dry-bulb temperature and relative humidity
Steam Table Interpolation Calculator
Interpolate saturated water properties (P_sat, v_f, v_g, h_f, h_fg, h_g, s_f, s_g) from built-in steam tables
Reynolds Number Calculator
Calculate Reynolds number and classify flow as laminar, transitional, or turbulent with common fluid presets
Bernoulli Equation Calculator
Solve for any unknown in the Bernoulli equation given pressure, velocity, and elevation at two points
Darcy-Weisbach Calculator
Calculate head loss and pressure drop in pipes using the Darcy-Weisbach equation with friction factor
Moody Chart Calculator
Calculate Darcy friction factor from Reynolds number and relative roughness using Colebrook-White and Swamee-Jain
Pump Power Calculator
Calculate hydraulic power, shaft power, and NPSH for centrifugal pumps from flow rate, head, and efficiency
Orifice Flow Calculator
Calculate volumetric flow rate through an orifice from discharge coefficient, area, and pressure drop
Manning Equation Calculator
Calculate open-channel flow rate and velocity for rectangular, trapezoidal, and circular cross-sections
Hydraulic Diameter Calculator
Calculate hydraulic diameter (D_h = 4A/P) for rectangular, circular, annular, and custom cross-sections
Drag Force Calculator
Calculate aerodynamic drag force and power from drag coefficient, fluid density, frontal area, and velocity
Buoyancy Calculator
Calculate buoyant force, submerged fraction, and whether an object floats or sinks in various fluids
Conduction Calculator
Calculate heat conduction through flat walls, cylinders, and spheres with multi-layer flat wall support
Convection Calculator
Calculate convective heat transfer Q = hA(T_surface - T_fluid) and solve for any unknown
Radiation Heat Transfer Calculator
Calculate radiative heat transfer Q = εσA(T₁⁴ - T₂⁴) with common emissivity reference values
Thermal Resistance Calculator
Build series/parallel thermal resistance networks for conduction, convection, and radiation elements
Fin Efficiency Calculator
Calculate fin efficiency and effectiveness for rectangular and annular fins using fin parameter m
Heat Exchanger LMTD Calculator
Calculate log-mean temperature difference and heat transfer rate for parallel and counter-flow heat exchangers
Heat Exchanger NTU Calculator
Calculate NTU, capacity ratio, and effectiveness for parallel flow, counter flow, and shell-and-tube heat exchangers
Lumped Capacitance Calculator
Calculate transient temperature response and time constant with Biot number validity check
Critical Insulation Radius Calculator
Calculate critical insulation radius for cylinders and spheres and determine if added insulation increases heat loss
Shaft Design Calculator
Design solid and hollow shafts under combined bending and torsion using ASME distortion energy criteria
Bearing Life Calculator
Calculate L10 bearing life in revolutions and hours for ball and roller bearings using basic dynamic load rating
Belt Drive Calculator
Calculate belt length, speed ratio, belt tensions, and required belt width for V-belt and flat-belt drives
Helical Spring Design Calculator
Calculate spring rate, deflection, and shear stress with Wahl correction factor for helical compression springs
Bolt Preload Calculator
Calculate bolt preload, torque requirements, and joint clamping force using the torque-tension relationship T = KFd
Weld Strength Calculator
Calculate allowable load and factor of safety for fillet and butt welds under shear, tension, and bending loads
Key and Keyway Calculator
Calculate shear and compressive stress in shaft keys and look up standard ANSI key sizes by shaft diameter
Flywheel Energy Calculator
Calculate kinetic energy stored, energy fluctuation, and required moment of inertia for flywheel design
Press Fit Calculator
Calculate interface pressure, hub hoop stress, and assembly force for press-fit shaft-hub connections using Lame's equations
Fatigue Life Calculator
Calculate factor of safety using Goodman, Soderberg, and Gerber criteria with modified endurance limit correction factors
Hardness Conversion Calculator
Convert between Rockwell C, Rockwell B, Brinell HB, Vickers HV, and approximate tensile strength using ASTM E140 data
Thermal Expansion Calculator
Calculate linear and volumetric thermal expansion ΔL = α·L₀·ΔT with presets for 10 common engineering materials
Stress-Strain Properties Calculator
Calculate modulus of resilience, approximate toughness, and elastic strain limit from E, σ_y, σ_UTS, and fracture strain
Material Comparison Calculator
Side-by-side comparison of two materials from 15 common engineering materials including density, E, σ_y, σ_UTS, α, k, and more
Creep Life Calculator
Calculate rupture time or allowable stress using the Larson-Miller parameter P = T(C + log₁₀(t_r))
Machining Parameters Calculator
Calculate cutting speed, feed rate, and MRR from diameter, RPM, feed per revolution, and depth of cut
Turning Operations Calculator
Calculate RPM, machining time, MRR, and cutting force for turning operations from workpiece geometry and cutting conditions
Drilling Calculator
Calculate RPM, feed rate, thrust force, torque, and machining time for drilling operations
Tolerance Stack-Up Calculator
Calculate worst-case and RSS statistical tolerance stack-up for multiple dimensions with bilateral tolerances
Surface Finish Calculator
Calculate theoretical Ra from feed and nose radius for turning; includes typical Ra values for common manufacturing processes
Linear Interpolation Calculator
Interpolate y from x using two or more data points with formula y = y₁ + (x-x₁)(y₂-y₁)/(x₂-x₁)
Bilinear Interpolation Calculator
Two-variable interpolation at a point (x,y) from four corner values — used for steam tables and two-variable data
Steam Table Lookup (Pressure)
Pressure-based saturated steam table lookup: enter P_sat → interpolated T_sat, v_f, v_g, h_f, h_fg, h_g, s_f, s_fg, s_g
Refrigerant R-134a Table Calculator
Saturated R-134a property lookup by temperature with interpolation: P_sat, h_f, h_g, s_f, s_g from -40 to 60°C
Unit Consistency Checker
Verify that engineering equations are dimensionally consistent using dropdowns for common physical quantities
Significant Figures Calculator
Count sig figs, round to N significant figures, and apply sig fig rules to addition, subtraction, multiplication, and division
Engineering Notation Calculator
Convert any number to scientific notation, engineering notation (exponent divisible by 3), and SI prefix form
Material Density Lookup
Searchable database of 30+ engineering materials with density in kg/m³, g/cm³, lb/ft³, and lb/in³